In early 2013, we began constructing a replacement template compiler in Java, Squarespace's main development language. The new compiler, now open sourced, was designed and implemented from scratch, which enabled several improvements to be made.

Automated UI tests are a crucial part of our QA process. Before going to production, we run a set of smoke tests which navigate around parts of the UI, recording screenshots and comparing them against a set of golden images. If a significant mismatch occurs, we consider the test failed and halt deploys while we investigate the issue.

Today, we’re announcing a new developer tool called the Squarespace Local Development Server. With it, developers can preview changes to template code locally (on their computer) before pushing them to a live website.

Data scientists, business operations, finance, and marketing teams are all working off our curated data stores to make critical decisions about the direction of the business, and there will inevitably come a time when somebody looks at a report and asks: "How do we know these numbers are correct?"

As a DIY platform, the approach Squarespace takes with taxes is to let merchants enter in the rates they need to collect, then provide a calculator that can apply those rates to a shopping cart. Squarespace’s role is thus not to know the exact details of a given tax system, but rather, to provide a tool that can effectively model the most common ones.